Hi Kees, I've been reminded that in 2.5 the slapo-otp(5) module (supports both TOTP and HMAC) was added, and we already ship that one in bookworm's slapd package. https://manpages.debian.org/bookworm/slapd/slapo-otp.5.en.html Could you please check whether slapo-otp(5) meets your needs? thanks, Ryan